ROR新手请教连mysql数据库的问题.

UserController:

class UserController < ApplicationController
 scaffold :user
end

database.yml:

# MySQL (default setup).  Versions 4.1 and 5.0 are recommended.
#
# Install the MySQL driver:
#   gem install mysql
# On MacOS X:
#   gem install mysql -- --include=/usr/local/lib
# On Windows:
#   gem install mysql
#       Choose the win32 build.
#       Install MySQL and put its /bin directory on your path.
#
# And be sure to use new-style password hashing:
#   http://dev.mysql.com/doc/refman/5.0/en/old-client.html
development:
  adapter: mysql
  database: demo
  username: root
  password: admin
  host: localhost

# Warning: The database defined as 'test' will be erased and
# re-generated from your development database when you run 'rake'.
# Do not set this db to the same as development or production.
test:
  adapter: mysql
  database: demo_test
  username: root
  password:
  host: localhost

production:
  adapter: mysql
  database: demo_production
  username: root
  password: 
  host: localhost

输入http://localhost:3000/user
出现的错误提示:
RuntimeError in UserController#index
Mysql not loaded
RAILS_ROOT: ./script/../config/..

Application Trace | Framework Trace | Full Trace
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:7:in `define_all_hashes_method!'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:60:in `require_mysql'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:78:in `mysql_connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:262:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:262:in `connection_without_query_cache='
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/query_cache.rb:54:in `connection='
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:230:in `retrieve_connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:78:in `connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/base.rb:760:in `columns'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:257:in `column_for'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:116:in `calculate'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:45:in `count'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:173:in `count_collection_for_pagination'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:197:in `paginator_and_collection_for'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:130:in `paginate'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/scaffolding.rb:108:in `list'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/scaffolding.rb:96:in `index'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:1095:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:1095:in `perform_action_without_filters'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:632:in `call_filter'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:634:in `call_filter'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:619:in `perform_action_without_benchmark'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/benchmarking.rb:66:in `perform_action_without_rescue'
c:/ruby/lib/ruby/1.8/benchmark.rb:293:in `measure'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/benchmarking.rb:66:in `perform_action_without_rescue'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/rescue.rb:83:in `perform_action'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:430:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:430:in `process_without_filters'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:624:in `process_without_session_management_support'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/session_management.rb:114:in `process'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:330:in `process'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/dispatcher.rb:41:in `dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:113:in `handle_dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:79:in `service'
c:/ruby/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
c:/ruby/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
c:/ruby/lib/ruby/1.8/webrick/server.rb:173:in `start_thread'
c:/ruby/lib/ruby/1.8/webrick/server.rb:162:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:162:in `start_thread'
c:/ruby/lib/ruby/1.8/webrick/server.rb:95:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:92:in `each'
c:/ruby/lib/ruby/1.8/webrick/server.rb:92:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:23:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:82:in `start'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:63:in `dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/commands/servers/webrick.rb:59
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:343:in `new_constants_in'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/commands/server.rb:39
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:343:in `new_constants_in'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
script/server:3
-e:4:in `load'
-e:4
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:7:in `define_all_hashes_method!'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:60:in `require_mysql'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:78:in `mysql_connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:262:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:262:in `connection_without_query_cache='
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/query_cache.rb:54:in `connection='
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:230:in `retrieve_connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:78:in `connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/base.rb:760:in `columns'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:257:in `column_for'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:116:in `calculate'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:45:in `count'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:173:in `count_collection_for_pagination'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:197:in `paginator_and_collection_for'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:130:in `paginate'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/scaffolding.rb:108:in `list'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/scaffolding.rb:96:in `index'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:1095:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:1095:in `perform_action_without_filters'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:632:in `call_filter'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:634:in `call_filter'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:619:in `perform_action_without_benchmark'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/benchmarking.rb:66:in `perform_action_without_rescue'
c:/ruby/lib/ruby/1.8/benchmark.rb:293:in `measure'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/benchmarking.rb:66:in `perform_action_without_rescue'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/rescue.rb:83:in `perform_action'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:430:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:430:in `process_without_filters'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:624:in `process_without_session_management_support'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/session_management.rb:114:in `process'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:330:in `process'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/dispatcher.rb:41:in `dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:113:in `handle_dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:79:in `service'
c:/ruby/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
c:/ruby/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
c:/ruby/lib/ruby/1.8/webrick/server.rb:173:in `start_thread'
c:/ruby/lib/ruby/1.8/webrick/server.rb:162:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:162:in `start_thread'
c:/ruby/lib/ruby/1.8/webrick/server.rb:95:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:92:in `each'
c:/ruby/lib/ruby/1.8/webrick/server.rb:92:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:23:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:82:in `start'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:63:in `dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/commands/servers/webrick.rb:59
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:343:in `new_constants_in'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/commands/server.rb:39
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:343:in `new_constants_in'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
script/server:3
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:7:in `define_all_hashes_method!'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:60:in `require_mysql'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/mysql_adapter.rb:78:in `mysql_connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:262:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:262:in `connection_without_query_cache='
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/query_cache.rb:54:in `connection='
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:230:in `retrieve_connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/abstract/connection_specification.rb:78:in `connection'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/base.rb:760:in `columns'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:257:in `column_for'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:116:in `calculate'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/calculations.rb:45:in `count'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:173:in `count_collection_for_pagination'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:197:in `paginator_and_collection_for'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/pagination.rb:130:in `paginate'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/scaffolding.rb:108:in `list'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/scaffolding.rb:96:in `index'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:1095:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:1095:in `perform_action_without_filters'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:632:in `call_filter'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:634:in `call_filter'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:619:in `perform_action_without_benchmark'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/benchmarking.rb:66:in `perform_action_without_rescue'
c:/ruby/lib/ruby/1.8/benchmark.rb:293:in `measure'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/benchmarking.rb:66:in `perform_action_without_rescue'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/rescue.rb:83:in `perform_action'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:430:in `send'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:430:in `process_without_filters'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/filters.rb:624:in `process_without_session_management_support'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/session_management.rb:114:in `process'
c:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.1/lib/action_controller/base.rb:330:in `process'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/dispatcher.rb:41:in `dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:113:in `handle_dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:79:in `service'
c:/ruby/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
c:/ruby/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
c:/ruby/lib/ruby/1.8/webrick/server.rb:173:in `start_thread'
c:/ruby/lib/ruby/1.8/webrick/server.rb:162:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:162:in `start_thread'
c:/ruby/lib/ruby/1.8/webrick/server.rb:95:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:92:in `each'
c:/ruby/lib/ruby/1.8/webrick/server.rb:92:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:23:in `start'
c:/ruby/lib/ruby/1.8/webrick/server.rb:82:in `start'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/webrick_server.rb:63:in `dispatch'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/commands/servers/webrick.rb:59
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:343:in `new_constants_in'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.1/lib/commands/server.rb:39
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:343:in `new_constants_in'
c:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.0/lib/active_support/dependencies.rb:496:in `require'
script/server:3
-e:4:in `load'
-e:4
Request
Parameters: None

Show session dump

---
flash: !map:ActionController::Flash::FlashHash {}


Response
Headers: {"cookie"=>[], "Cache-Control"=>"no-cache"}

我建的表名为:users,而且有一个id为自动增加的.

我用下面的程序测试是可以连数据库的:

require_gem "mysql"
begin
  dbh=Mysql.real_connect("localhost","root","admin","demo",3306)
  dbh.query("drop table if exists test_rb")
  dbh.query("create table test_rb(id int,name varchar(20))")
  dbh.query("insert into test_rb values(1,'ss')")
  dbh.query("insert into test_rb values(1,'aaa')")
  printf "%d rows were inserted\n",dbh.affected_rows
  
  res=dbh.query("SELECT name FROM test_rb")
  puts "===============\n"
  while row=res.fetch_row do
  printf "%s,%s\n",row[0],row[1]
  end
  puts "================\n"
  puts "Server version:"+dbh.get_server_info
  rescue Mysql::Error=>e
  puts "Error code:#{e.errno}"
  puts "Error message:#{e.error}"
  puts "Error SQLSTATE:#{e.sqlstate}" if e.respond_to?("sqlstate")
  ensure
  dbh.close if dbh
 end

楼主怎么解决这个问题的？我也出现了